The conventional method for cleaning the outer glazed surfaces of sealed windows of high rise buildings is by means of a manual operation by workers in a swing stage (sometimes referred to as a cradle or balcony) which the workers can raise or lower along the side of the building to a position opposite the window glaze to be cleaned. The conventional cleaning method involves two steps. First, the glazed surface is brushed or scrubbed with a cleaning brush soaked in cleaning fluid. This step is followed by a squeegeeing or scraping operation in which the workers, using a plastic or rubber blade (squeegee) scrape all excess liquid from the glaze surface leaving it in a streak free pristine condition. In the case of buildings of intermediate height the same cleaning operation is sometimes performed by workers lowered over the side of the building in bosun chairs. Both methods of cleaning outer glazed surfaces are expensive and constitute one of the most dangerous occupations in industry.
There is a well known need for a window glaze cleaning device for cleaning glazed surfaces that are not readily accessible, such as the glazed outer surfaces of sealed windows of high rise buildings which is efficient and does not require workers on the outside of the building.